Now, I want to find out division for YTD Leads for 2007 and 2006.
I have used this syntax = Where ( =2007) / Where ( = 2006) . It works good.

How to make this generic, I mean by using current year or previous year, as next year the formula will change to Leads ytd(2008) / leads ytd(2007)
I am a little lost how to do this.

How many years of information you are going to display in the report…

If you have variable # of years then it is difficult. You have to create local variables for your years…like first extract the year and subtract 1 or 2 or 3 to get previous years.

But you need variables… locally declared in your report.